Chemical changes are
non-reversible
reversible
sometimes reversible
What is always formed from a chemical change?
Light
Anew substance
A colour change
Which of these is not an example of a chemical change?
An explosion
Rusting
Freezing
If a piece of wood breaks, what type of change is it?
Chemical change
Physical change
Both of them
Which of these is a physical change?
Cooking eggs
Burning wood
Water turns into ice
Which of these chemical changes occur s in the absence of oxygen?
Oxidation
Fermentation
Combustion
Which of these chemical changes transforms the substances into rust?
What is needed, as well as oxygen, in the process of combustion?
Bacteria
Fuel
None of them
Circle the foods that are made by fermentation.
Salad and fried chiken
Wine and cheese
Popcorn and coke
Combustion produces:
Light and heat
Sound
Electricity